Imaging findings of pelvic venous insufficiency in patients with postural orthostatic tachycardia syndrome

OBJECTIVES

Some patients with postural orthostatic tachycardia syndrome (POTS) demonstrate improved dysautonomic symptoms following treatment for pelvic venous insufficiency (PVI). This study assessed the prevalence of significant left common iliac vein (LCIV) compression in POTS patients.

METHODS

Radiologists retrospectively reviewed CT images of pelvic veins for 216 women (191 with POTS and 25 age-comparable controls).Quantitative vascular analysis identified percent-diameter compression of the LCIV by the right common iliac artery. Significant LCIV compression was defined as >50%.

RESULTS

Significant LCIV compression was found in 69% (131/191) of females with POTS versus 40% (10/25) in controls. The hypothesis that venous compression and presence of POTS are independent was rejected (p = .005).

CONCLUSIONS

Significant LCIV compression was noted in a majority of female POTS patients, suggesting that incidence of iliac venous obstruction may be higher than the general population. Patients with POTS and symptoms of PVI may benefit from assessment for venous outflow obstruction.

Food Sensitivity Testing and Elimination Diets in the Management of Irritable Bowel Syndrome

The nonpharmacologic management of irritable bowel syndrome focuses on dietary modification through the concept of food sensitivity or intolerance. Currently, testing for food allergies is not recommended in the absence of a clinical history consistent with an immunoglobulin E–mediated reaction. Objective means of determining food sensitivity, such as individualized diets, are being studied, but testing for food sensitivity is limited to certain food groups. Diets such as the low-FODMAPs (fermentable oligosaccharides, disaccharides, monosaccharides, and polyols) diet may provide benefit.

Results of ambulatory pH monitoring do not reliably predict response to therapy in patients with eosinophilic oesophagitis

BACKGROUND

The consensus statements for eosinophilic oesophagitis recommend that ambulatory pH monitoring is one means of determining if gastro-oesophageal reflux is the cause of oesophageal eosinophilia and should guide pharmacological therapy.

AIM

To evaluate prospectively the accuracy of pH monitoring as a predictor of endoscopic, histological and symptomatic response in patients with oesophageal eosinophilia.

METHODS

We conducted a prospective trial in which patients with oesophageal eosinophilic infiltration with ≥15 eos/hpf underwent a 24-h pH study and were placed in one of two treatment arms for 6 weeks based on positive or negative results. Patients with abnormal acid exposure were treated with esomeprazole 40 mg twice daily and others were treated with oral viscous budesonide 1 g twice daily. Response to treatment was assessed by oesophageal histology (<5 eos/hpf) and symptoms.

RESULTS

A total of 51 patients were enrolled in the study. The average patient age was 39 years and 31 patients (61%) were male. The average number of eosinophils per hpf, prior to study enrolment was 41.2 (range 15-140, s.d. 27.7). Nineteen (37%) had positive pH studies and 32 (63%) had negative pH studies. Eighteen patients completed treatment with esomeprazole. Only eleven (61%) had histological response and, of these eleven, five (46%) had symptomatic improvement. A total of 28 patients with normal acid exposure completed treatment with budesonide. Only 16 (57%) had histological and 11 (69%) had symptomatic improvement.

CONCLUSION

In this prospective trial of pH-guided treatment, neither positive nor negative results of initial pH monitoring accurately predicted response to therapy.

Serologic profiles aiding the diagnosis of autoimmune gastrointestinal dysmotility

BACKGROUND & AIMS

Autoimmune gastrointestinal dysmotility is a limited autoimmune dysautonomia occurring idiopathically or in the context of an anatomically remote neoplasm, previously documented or unsuspected. Here we report 24 Mayo Clinic patients in whom the profile of serum autoantibodies aided this diagnosis.

METHODS

All patients were ascertained serologically in the course of service evaluation for autoantibodies consistent with neurologic autoimmunity. Review of their histories, motility studies, and laboratory findings revealed that all had presented with subacute gastrointestinal dysmotility.

RESULTS

Recorded motility abnormalities included esophageal dysmotility 8 (6 had achalasia), delayed gastric emptying 12, slow small intestinal transit 7, slow colonic transit 4, and pelvic floor dyssynergia 4. Four patients underwent abdominal surgery; 2 commenced total parenteral nutrition. Plasma membrane cation channel autoantibodies were detected in 23 patients: neuronal voltage-gated calcium channel (5 N-type and 1 P/Q-type), acetylcholine receptor (11 ganglionic-type and 4 muscle-type), and neuronal voltage-gated potassium channel autoantibodies (4). Two patients had antineuronal nuclear autoantibodies, type 1. Approximately half of the patients had neural autoantibodies (including skeletal muscle striational and glutamic acid decarboxylase, 65kd isoform) or other antibody markers of organ-specific autoimmunity (thyroid or gastric parietal cell specificities). Neoplasia was diagnosed in 11 patients (9 recent, 2 remote): lung, breast and endometrial, gastrointestinal and thymoma. Moderate to dramatic improvement in gastrointestinal symptoms was reported after immunotherapy in 4 of 4 patients treated and after pyridostigmine treatment in 2 of 2 patients treated.

CONCLUSIONS

Autoimmune serology aids the diagnosis of autoimmune gastrointestinal dysmotility, both paraneoplastic and idiopathic, and might guide management.

Effect of 5 days linaclotide on transit and bowel function in females with constipation-predominant irritable bowel syndrome

BACKGROUND & AIMS

Oral linaclotide, a novel agonist of guanylate cylase-C, stimulates intestinal fluid secretion and transit, and decreases visceral hypersensitivity in animal studies. In healthy volunteers, linaclotide was safe, well tolerated, increased stool frequency, and decreased stool consistency and time to first bowel movement. This randomized, double-blind, placebo-controlled study evaluated the effects of oral linaclotide, 100 and 1000 microg once daily, in 36 women with constipation-predominant irritable bowel syndrome; colonic transit was normal in >50% patients.

METHODS

Participants underwent 5-day baseline and 5-day treatment periods; gastrointestinal transit (by validated scintigraphy) and bowel function (by daily diaries) were assessed. Treatment effects were compared using analysis of covariance (baseline colonic transit as covariate) with pairwise comparisons of each dose vs placebo.

RESULTS

There was a significant overall treatment effect on ascending colon emptying half-time (P = .015) and overall colonic transit at 48 hours (P = .02) but not overall transit at 24 hours (P = ns), with a significant acceleration by linaclotide 1000 microg vs placebo (P = .004 and P = .01, respectively) but no significant effect of linaclotide 100-microg dose. There were significant overall treatment effects on stool frequency, stool consistency, ease of passage, and time to first bowel movement with a strong dose response for stool consistency (overall, P < .001). No safety issues were identified.

CONCLUSIONS

In women with constipation-predominant irritable bowel syndrome, linaclotide 1000 microg once daily significantly accelerated ascending colonic transit and altered bowel function. Further randomized controlled trials of clinical efficacy of linaclotide are warranted.

IBS--review and what's new

Irritable bowel syndrome (IBS) is a highly prevalent gastrointestinal motility disorder broadly characterized by abdominal pain/discomfort associated with altered bowel habits. The chronic and bothersome nature of IBS symptoms often negatively affects patient quality of life and activity level and places a substantial economic burden on patients and the healthcare system. Advances in research have led to a greater understanding of the underlying pathophysiology of IBS, particularly regarding the role serotonin plays in the gastrointestinal tract; the development of stepwise, symptom-based diagnostic strategies that allow for a diagnosis of IBS to be made without the need for extensive laboratory testing; and the development of treatment options targeting underlying pathophysiologic mechanisms that provide relief of the multiple symptoms associated with IBS. This review highlights recent advances in research and discusses how these findings can be applied to daily clinical practice.

Effect of somatostatin analog on postprandial satiation in obesity

OBJECTIVE

Altered satiation may impact postprandial symptoms and potentially change food intake in obesity. Our aim was to compare effects of octreotide and placebo on postprandial symptoms, satiation, and gastric volumes in obesity.

RESEARCH METHODS AND PROCEDURES

In a randomized, parallel-group, double-blind, placebo-controlled study, 26 obese but otherwise healthy participants received 100 mug of octreotide or placebo subcutaneously 30 minutes before each study. Studies were performed on 2 separate days and included validated non-invasive techniques: (99m)Tc-single photon emission computed tomography imaging to measure fasting stomach volume and gastric volume changes after 90 mL of water and 240 mL of Ensure and a standardized nutrient drink test to measure the maximum tolerated volume and postprandial symptoms.

RESULTS

Relative to placebo, octreotide increased gastric volume after 90 mL of water; however, fasting and gastric volume change post-Ensure and maximum tolerated volume of Ensure were not different. Octreotide decreased sensations of fullness (p = 0.035) and bloating (p = 0.05) and tended to reduce aggregate symptoms (p = 0.07) after the fully satiating meal.

DISCUSSION

In obese individuals, somatostatin analog significantly reduced postprandial sensations after a satiating meal without altering maximum tolerated meal volume or postnutrient gastric volume, suggesting an effect on upper gut sensation. The role of somatostatin as a permissive factor in the development of obesity by reducing postprandial sensations deserves further study.

Effect of renzapride on transit in constipation-predominant irritable bowel syndrome

BACKGROUND & AIMS

The aim of this study was to evaluate the dose-ranging pharmacodynamic effects of renzapride, a 5-hydroxytryptamine 4 (5-HT4) receptor full agonist/5-HT3 receptor antagonist, on gastrointestinal transit and symptoms in patients with constipation-predominant irritable bowel syndrome (C-IBS).

METHODS

Forty-eight patients (46 women) with C-IBS underwent recording of baseline symptoms for 1 week. Twelve patients per group were randomized (double-blind, parallel design) to 11-14 days of renzapride (1, 2, or 4 mg) or placebo, once daily. Daily bowel habits and weekly satisfactory relief of IBS symptoms were recorded. At the end of treatment, gastric emptying (GE), small bowel transit (SBT), and colon transit (CT) were measured by scintigraphy. The relationship between CT and bowel function was evaluated.

RESULTS

A statistically significant linear dose response to renzapride was detected for CT (GC8 h, P = 0.004; GC24 h, P = 0.056), and ascending colon (AC) emptying t1/2 (P = 0.019), but not for GE (t1/2, P = 0.088; or SBT, P = 0.41). AC half-time transit (t1/2) for placebo and 4 mg of renzapride were (median) 17.5 vs. 5.0 hours, respectively. Improved bowel function scores (stool form and ease of passage, but not frequency) were significantly (P < 0.05) associated with accelerated CT. Pharmacokinetic analysis showed linear kinetics of renzapride with a mean t1/2 in plasma of 10 hours. Bowel function and satisfactory relief were not significantly altered by renzapride, although a type II error cannot be excluded. No significant adverse clinical, laboratory, or electrocardiogram (ECG) effects were observed.

CONCLUSIONS

Renzapride causes clinically significant dose-related acceleration of CT, particularly ascending colonic emptying; this acceleration of transit is associated with improvement of bowel function in female C-IBS patients.

Comparison of gastric volumes in response to isocaloric liquid and mixed meals in humans

AIMS

To compare gastric volume responses to ingestion of isocaloric liquid or mixed (solid-liquid) meals and document the intra- and interindividual reproducibility of gastric volume measurement using single photon emission computed tomography (SPECT) imaging after i.v. 99mTc-pertechnetate.

METHODS

Eight healthy volunteers performed two studies at least 9 months apart. Gastric volumes were measured after a 317 kcal liquid nutrient meal. Within 2 weeks of the second liquid meal study, participants performed a third study, ingesting an isocaloric mixed meal. The order of the mixed and second liquid meals was randomized; Bland-Altman plot displayed data on repeated studies with liquid meal and paired t-test compared gastric volumes after mixed or liquid isocaloric meals.

RESULTS

Fasting and postprandial gastric volumes associated with the two liquid meals were not significantly different; inter- and intra-individual coefficients of variation were 13 and 13.8%. In response to the mixed meal, there was a lower absolute postprandial volume and lower change in gastric volume over fasting volume compared with the response to the liquid meal (P = 0.0001).

CONCLUSION

The SPECT measurement of gastric volumes in response to a nutrient liquid meal is reproducible. The magnitude of the volume response is greater after the liquid meal compared with the isocaloric mixed meal.

Chronic Intestinal Pseudoobstruction

Patients with chronic intestinal pseudoobstruction (CIP) experience a constellation of symptoms including abdominal pain, nausea, fullness, and malaise which fluctuates in severity and invariably result in a diminished quality of life. Though surgical resection or transplantation may be an option for some, there currently is no cure for CIP. Thus, management strategies utilize pharmacologic, intravenous, endoscopic, and surgical techniques to promote transit, minimize painful bloating, reduce complications of stasis, and improve quality of life. Prokinetic agents such as erythromycin, metoclopramide, cisapride, neostigmine, and tegaserod may be effective for acute exacerbations. Octreotide may reduce symptoms of bacterial overgrowth and bloating by stimulating migrating motor complexes. Enteral tubes for venting and nutritional support may reduce hospitalizations. Total parenteral nutrition (TPN), fraught with well-known complications, may be the only tolerated source for nutrients and fluid. Advanced disease may magnify nutritional problems, difficulties of long term intravenous and intestinal access, and poor symptom control. Because the initial process may manifest in other intestinal regions following surgery, resection of involved segments should be performed with caution. Small intestinal transplantation is a high-risk surgery performed in persons unable to tolerate intravenous (IV) nutrition. Optimal management for persons with CIP should not only provide nutritional and symptom focused care but should be part of a supportive network which links patients to their appropriate healthcare needs.

Effect of a somatostatin analogue on gastric motor and sensory functions in healthy humans

BACKGROUND

Pharmacological approaches to alter satiation may have an impact on functional upper gastrointestinal disorders and potentially change food intake in obesity.

AIM

Our aim was to compare the effects of two doses of octreotide and placebo on postprandial symptoms, gastric accommodation, and gastric emptying using validated non-invasive techniques.

METHODS

In a randomised, parallel group, two dose, double blind, placebo controlled study, 39 healthy participants (13 per group) were randomised to 30 or 100 micro g octreotide or placebo, administered subcutaneously, 30 minutes before each study. Studies were performed on three separate days and included scintigraphic gastric emptying of solids and liquids, (99m)Tc SPECT imaging to measure fasting stomach volume and gastric accommodation following a 300 ml Ensure meal, and a standardised nutrient drink test to measure maximum tolerated volume and postprandial symptoms.

RESULTS

Relative to placebo, both doses of octreotide delayed gastric emptying of solids (not liquids), increased fasting gastric volume, reduced the change in gastric volume post meal, and decreased the sensation of fullness after a satiating meal.

CONCLUSION

The somatostatin analogue octreotide significantly alters human gastric functions, including inhibition of the normal reflex responses of gastric volume increase and emptying of the meal. These pharmacological effects suggest studies of the medication in disorders of satiation, including obesity and dyspepsia, are warranted.

Incidence, risk factors, and outcomes of fecal incontinence after acute brain injury: findings from the Traumatic Brain Injury Model Systems national database

OBJECTIVE

To investigate the incidence, risk factors, and outcome in patients with fecal incontinence after acute brain injury.

DESIGN

A retrospective study of the incidence of and risk factors contributing to fecal incontinence, and outcomes at admission to and discharge from inpatient rehabilitation and at 1-year follow-up.

SETTING

Medical centers in the federally sponsored Traumatic Brain Injury Model Systems (TBIMS).

PARTICIPANTS

A total of 1,013 consecutively enrolled rehabilitation inpatients from 17 TBIMS centers who were admitted to acute care within 24 hours of traumatic brain injury and seen at 1-year postinjury between 1990 and 2000.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

Incidence of fecal incontinence, length of coma, length of posttraumatic amnesia (PTA), admission Glasgow Coma Scale (GCS) score, length of stay (LOS), FIM instrument scores, disposition at discharge and follow-up, and incidences of pelvic fracture, frontal contusion, and urinary tract infection (UTI).

RESULTS

The incidence of fecal incontinence was 68% at admission to inpatient rehabilitation, 12.4% at rehabilitation discharge, and 5.2% at 1-year follow-up. Analysis of variance and chi-square analyses revealed statistically significant associations between the incidence of fecal incontinence at rehabilitation admission and admission GCS score, length of coma and PTA, LOS, and incidence of UTI and frontal contusion. Fecal incontinence at rehabilitation discharge was significantly associated with several variables, including age, discharge disposition, admission GCS score, length of coma, PTA, LOS, FIM scores, and incidence of pelvic fracture and frontal contusion. Significant associations were also found between fecal incontinence at 1-year follow-up and age, discharge and current 1-year disposition, admission GCS score, length of coma, LOS, FIM scores, and incidence of UTI (P<.05). Although logistic regression analyses were significant (P<.001), and predicted continence with 100% accuracy, demographics, injury characteristics, medical complications, and functional outcomes did not predict incontinence at discharge and at 1-year follow-up.

CONCLUSIONS

Fecal incontinence is a significant problem after brain injury. Certain factors may increase its likelihood. Further studies evaluating mechanisms of fecal incontinence and treatment or control interventions would be useful.

Assessment of human colon cancer protein kinetics in vivo

BACKGROUND

Malignancies enlarge because protein synthesis exceeds the rate of breakdown; however, the specific protein kinetic pattern remains unknown. Determining in vivo protein kinetic rates for a tumor may be useful for quantifying individual responses to a specific therapy. The aim of this study was to assess whether the growth of tumors is related to an increase in protein synthesis or an inhibition of protein breakdown.

METHODS

Five patients (age, 59 +/- 3 years) with adenocarcinoma of the colon undergoing colonoscopy were studied. Tissue protein synthesis and breakdown rates were measured in vivo for both segments of colon cancer and adjacent normal-appearing colonic mucosa by using a primed, continuous infusion of 1(13)C leucine with tissue biopsy and quantitation of regional blood flow by laser Doppler flowmetry.

RESULTS

Segments of colon cancer had a significantly (p < 0.05) greater rate of protein synthesis as quantitated by both the fractional rate of protein synthesis (Ca 45.4% +/- 5.0%/day versus nl mucosa 35.7% +/- 3.1%/day; mean +/- SEM) and by the tissue synthesis rate (Ca 69.4 +/- 9.0 versus nl mucosa 51.6 +/- 5.2 mumol/L leucine/day/100 gm tissue). Regional blood flow was significantly elevated in the cancer (Ca 110.9 +/- 5.8 versus nl mucosa 91.2 +/- 2.9 ml/min/100 gm), which contributed to commensurate rates of tissue breakdown (Ca 28.6 +/- 2.0 versus nl mucosa 28.2 +/- 2.4 mumol/L leucine/day/100 gm).

CONCLUSIONS

These results illustrate that human colon cancers grow in vivo as a result of increases in protein synthesis. Furthermore, increases in regional blood flow limit the rate of tissue protein breakdown of colon cancer, thereby contributing to growth of the malignancy. These findings support the contention that therapeutic strategies aimed at negating this inherent increase in protein synthesis or limiting blood flow may effectively limit the growth of malignancies. This methodology may also provide an index for evaluating the effectiveness of future therapies aimed at reducing tumor growth for individual patients.

Antibiotics and pancreatitis

Despite improvements in the general supportive care of patients with acute pancreatitis, the morbidity of infectious complications remains high and bacterial infections account for most deaths. The role of antibiotics in reducing infectious morbidity and mortality has been debated for decades because of a lack of supportive clinical data. Research completed over the past decade has helped to define the microbiology, establish the risk factors, and improve the understanding of the pathogenesis of infectious complications in patients with acute pancreatitis. Patients with acute necrotizing pancreatitis are at the greatest risk of developing an infection with enteric gram-negative or gram-positive bacteria translocated from the bowel lumen into the necrotic pancreatic tissue. The most effective antimicrobial agents are the fluoroquinolones, imipenem-cilastatin, and metronidazole, which achieve adequate penetration into pancreatic juice and necrotic tissue and inhibit the growth of enteric bacteria. Animal and human studies support the use of antibiotics for the prevention of infectious morbidity and mortality in severe acute pancreatitis. Recent clinical trials have assessed the role of both systemic antibiotic prophylaxis and selective bowel decontamination with nonabsorbable oral antimicrobials in high-risk patients with acute necrotizing pancreatitis. This article provides an overview of our current knowledge of pancreatic infections and a critical analysis of studies on the role of antibiotics in this disease.

Percutaneous endoscopic gastrojejunostomy: a dual center safety and efficacy trial

Although jejunal tube placement through a percutaneous endoscopic gastrostomy (PEG) has not been proven to be preferable to PEG feeding, it would be theoretically advantageous for those patients prone to gastrointestinal aspiration. However, reliable placement of a small bowel feeding tube through a PEG has been technically difficult. We have previously reported successful placement of a percutaneous endoscopic gastrojejunostomy (PEG/J) with minimal complications. These results are in contrast to other series that report technical difficulty, frequent tube dysfunction and gastric aspiration. We describe an over-the-wire PEG/J technique performed by multiple operators at two medical centers. Gastrostomy tube placement was successful in 94% of patients. Initial placement of the jejunal tube was successful in 88% of patients. Second attempts were 100% successful. The average procedure time was 36 minutes. The distal duodenal and jejunal placement of the jejunal tube resulted in no episodes of gastroduodenal reflux. Complications included jejunal tube migration (6%), clogging (18%), and unintentional removal (11%). The majority of patients were ultimately converted to either oral or intragastric feedings. We conclude that the PEG/J system is a reliable, reproducible method of small bowel feeding and is associated with no episodes of tube feeding reflux when the jejunal tube is positioned in the distal duodenum or beyond. Furthermore, it provides a temporary nutritional bridge for those patients who are later transitioned to either PEG or oral feeding.

Overzealous resuscitation of an extremely malnourished patient with nutritional cardiomyopathy

Overzealous resuscitation of the severely malnourished patient may be associated with life-threatening complications. A variety of electrolyte, hemodynamic, septic, and nutritional derangements may result in sudden decompensation and even death. We present a case that dramatically illustrates these complications and focuses on the key role of underlying nutritional cardiomyopathy.